(CBS DETROIT) - Former congressman Justin Amash, who left the republican party after supporting the impeachment of then-president Donald Trump is considering a run for Michigan's soon-to-be vacant senate seat.

Amash posted on social media that he was launching an exploratory committee and would run as a Republican, calling the current field of candidates, "un-inspired, un-serious, and un-prepared."

Amash was a five-term congressman from Grand Rapids who represented Michigan's 3rd district from 2011 to 2021.

After leaving the GOP and becoming a libertarian, Amash announced he would not seek re-election.

He has not given a timeline as to when he'll make the decision to join the race.